Tetra­kis(acetonitrile-κN)lithium hexa­fluoridophosphate acetonitrile monosolvate

Seo, D.M.; Boyle, P.D.; Henderson, W.A.

doi:10.1107/S1600536811027528

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 8| August 2011| Page m1148

doi:10.1107/S1600536811027528

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Tetrakis(acetonitrile-κN)lithium hexafluoridophosphate acetonitrile monosolvate

Daniel M. Seo,^a ^* Paul D. Boyle ^b and Wesley A. Henderson ^a

^aDepartment of Chemical & Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA, and ^bDepartment of Chemistry, North Carolina State University, Raleigh, NC 27695, USA
^*Correspondence e-mail: wesley_henderson@ncsu.edu

(Received 23 June 2011; accepted 9 July 2011; online 30 July 2011)

In the title compound, [Li(CH₃CN)₄]PF₆·CH₃CN, the asymmetric unit consists of three independent tetrahedral [Li(CH₃CN)₄]⁺ cations, three uncoordinated PF₆⁻ anions and three uncoordinated CH₃CN solvent molecules. The three anions are disordered over two sites through a rotation along one of the F—P—F axes. The relative occupancies of the two sites for the F atoms are 0.643 (16):0.357 (16), 0.677 (10):0.323 (10) and 0.723 (13):0.277 (13). The crystal used was a racemic twin, with approximately equal twin components.

Related literature

For solvates structures with the PF₆⁻ anion, see: Zavalij et al. (2004 ); Armstrong et al. (1998 ); Black et al. (1995 ). For solvate structures of CH₃CN with lithium salts, see: Seo et al. (2011a ,b ); Klapötke et al. (2006 ); Brooks et al. (2002 ); Yokota et al. (1999 ); Raston et al. (1989 ).

Experimental

Crystal data

[Li(C₂H₃N)₄]PF₆·C₂H₃N
M_r = 357.18
Orthorhombic, P 2₁ 2₁ 2₁
a = 8.6064 (3) Å
b = 21.9864 (8) Å
c = 27.8721 (10) Å
V = 5274.1 (3) Å³
Z = 12
Mo Kα radiation
μ = 0.22 mm⁻¹
T = 110 K
0.67 × 0.40 × 0.27 mm

Data collection

Bruker–Nonius Kappa Axis X8 APEXII diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.870, T_max = 0.944
128974 measured reflections
17572 independent reflections
13189 reflections with I > 2σ(I)
R_int = 0.060

Refinement

R[F² > 2σ(F²)] = 0.054
wR(F²) = 0.157
S = 1.03
17572 reflections
749 parameters
H-atom parameters constrained
Δρ_max = 0.46 e Å⁻³
Δρ_min = −0.31 e Å⁻³
Absolute structure: Flack (1983 ), 7916 Friedel pairs
Flack parameter: 0.45 (7)

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: cif2tables.py (Boyle, 2008 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811027528/fj2439sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811027528/fj2439Isup2.hkl

checkCIF report

Comment top

LiPF₆ is the most widely used lithium salt for electrolytes in commercial Li-ion batteries. Little information is available regarding the interactions of the ions and solvent molecules within electrolytes. Crystal structures, however, provide useful models for these interactions. The structure of [Li(CH₃CN)₄]PF_6.CH₃CN is therefore reported here as part of an extensive study exploring solvate structures present in nitrile mixtures with lithium salts.

Related literature top

For solvates structures with the PF₆^- anion, see: Zavalij et al. (2004); Armstrong et al. (1998); Black et al. (1995). For solvate structures of CH₃CN with lithium salts, see: Seo et al. (2011a,b); Klapötke et al. (2006); Brooks et al. (2002); Yokota et al. (1999); Raston et al. (1989).

Experimental top

LiPF₆ (99.99%) was purchased from Sigma-Aldrich and used as-received. Anhydrous acetonitrile (Sigma Aldrich, 99.8%) was used as-received. In a Vacuum Atmospheres inert atmosphere (N₂) glove box (< 5 p.p.m. H₂O), LiPF₆ (0.2 mmol) and acetonitrile (2 mmol) were sealed in a vial and heated on a hot plate to form a homogeneous solution. Upon standing at ambient temperature, colorless plate single crystals suitable for analysis formed.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: cif2tables.py (Boyle, 2008).

Figures top

	Fig. 1. Molecular structure of the title compound. The thermal ellipsoids are shown at a 50% probability level.
	Fig. 2. Packing diagram for the title compound (Li-purple; P-gold; F-green; N-blue).

Tetrakis(acetonitrile-κN)lithium hexafluorophosphate acetonitrile monosolvate top

Crystal data top

[Li(C₂H₃N)₄]PF₆·C₂H₃N	F(000) = 2184
M_r = 357.18	D_x = 1.349 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 9760 reflections
a = 8.6064 (3) Å	θ = 2.9–25.3°
b = 21.9864 (8) Å	µ = 0.22 mm⁻¹
c = 27.8721 (10) Å	T = 110 K
V = 5274.1 (3) Å³	Prism, colourless
Z = 12	0.67 × 0.40 × 0.27 mm

Data collection top

Bruker–Nonius Kappa Axis X8 APEXII diffractometer	17572 independent reflections
Radiation source: fine-focus sealed tube	13189 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.060
ω and ϕ scans	θ_max = 31.6°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −12→12
T_min = 0.870, T_max = 0.944	k = −32→32
128974 measured reflections	l = −40→40

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.054	H-atom parameters constrained
wR(F²) = 0.157	w = 1/[σ²(F_o²) + (0.0925P)² + 0.5839P] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max = 0.001
17572 reflections	Δρ_max = 0.46 e Å⁻³
749 parameters	Δρ_min = −0.31 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 7916 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.45 (7)

Crystal data top

[Li(C₂H₃N)₄]PF₆·C₂H₃N	V = 5274.1 (3) Å³
M_r = 357.18	Z = 12
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 8.6064 (3) Å	µ = 0.22 mm⁻¹
b = 21.9864 (8) Å	T = 110 K
c = 27.8721 (10) Å	0.67 × 0.40 × 0.27 mm

Data collection top

Bruker–Nonius Kappa Axis X8 APEXII diffractometer	17572 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	13189 reflections with I > 2σ(I)
T_min = 0.870, T_max = 0.944	R_int = 0.060
128974 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.054	H-atom parameters constrained
wR(F²) = 0.157	Δρ_max = 0.46 e Å⁻³
S = 1.03	Δρ_min = −0.31 e Å⁻³
17572 reflections	Absolute structure: Flack (1983), 7916 Friedel pairs
749 parameters	Absolute structure parameter: 0.45 (7)
0 restraints

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Li1	0.4767 (5)	0.24443 (16)	0.92740 (13)	0.0283 (7)
N1	0.3918 (2)	0.24237 (9)	0.86018 (7)	0.0315 (4)
C1	0.3294 (3)	0.24034 (10)	0.82412 (8)	0.0270 (4)
C2	0.2510 (3)	0.23804 (13)	0.77846 (9)	0.0395 (6)
H2A	0.2308	0.2795	0.7672	0.059*
H2B	0.1524	0.2163	0.7820	0.059*
H2C	0.3166	0.2168	0.7551	0.059*
N2	0.3962 (3)	0.32101 (8)	0.96007 (7)	0.0309 (4)
C3	0.3370 (3)	0.35994 (9)	0.97954 (8)	0.0268 (4)
C4	0.2623 (3)	0.40922 (12)	1.00584 (9)	0.0373 (5)
H4A	0.1497	0.4026	1.0064	0.056*
H4B	0.2850	0.4480	0.9900	0.056*
H4C	0.3019	0.4102	1.0388	0.056*
N3	0.7092 (3)	0.23919 (9)	0.93095 (7)	0.0337 (4)
C5	0.8413 (3)	0.24082 (10)	0.93095 (8)	0.0273 (4)
C6	1.0104 (3)	0.24217 (11)	0.93078 (9)	0.0333 (5)
H6A	1.0480	0.2546	0.9625	0.050*
H6B	1.0466	0.2712	0.9066	0.050*
H6C	1.0504	0.2016	0.9232	0.050*
N4	0.3809 (2)	0.17257 (9)	0.96466 (7)	0.0317 (4)
C7	0.3163 (3)	0.13237 (9)	0.98013 (8)	0.0272 (4)
C8	0.2329 (3)	0.08021 (12)	0.99953 (9)	0.0355 (5)
H8A	0.1609	0.0645	0.9753	0.053*
H8B	0.1745	0.0927	1.0281	0.053*
H8C	0.3073	0.0483	1.0083	0.053*
Li2	0.4831 (5)	0.07850 (16)	0.55254 (14)	0.0317 (8)
N5	0.5941 (2)	0.08137 (10)	0.48759 (7)	0.0362 (4)
C9	0.6478 (3)	0.08505 (10)	0.45077 (8)	0.0294 (4)
C10	0.7130 (3)	0.08955 (12)	0.40250 (8)	0.0344 (5)
H10A	0.6803	0.0543	0.3835	0.052*
H10B	0.8266	0.0905	0.4045	0.052*
H10C	0.6757	0.1269	0.3871	0.052*
N6	0.2498 (3)	0.07967 (9)	0.54441 (7)	0.0335 (4)
C11	0.1191 (3)	0.07718 (10)	0.54844 (8)	0.0289 (4)
C12	−0.0483 (3)	0.07269 (12)	0.55341 (10)	0.0392 (6)
H12A	−0.0962	0.0714	0.5215	0.059*
H12B	−0.0873	0.1081	0.5710	0.059*
H12C	−0.0745	0.0355	0.5711	0.059*
N7	0.5280 (3)	0.15207 (10)	0.59300 (8)	0.0391 (5)
C13	0.5289 (3)	0.19443 (10)	0.61689 (8)	0.0316 (5)
C14	0.5297 (3)	0.24825 (11)	0.64738 (9)	0.0378 (5)
H14A	0.4770	0.2391	0.6777	0.057*
H14B	0.4755	0.2815	0.6311	0.057*
H14C	0.6373	0.2604	0.6539	0.057*
N8	0.5384 (3)	0.00158 (9)	0.58959 (8)	0.0386 (5)
C15	0.5484 (3)	−0.04007 (10)	0.61326 (8)	0.0311 (5)
C16	0.5610 (4)	−0.09365 (11)	0.64400 (9)	0.0395 (6)
H16A	0.6246	−0.0838	0.6721	0.059*
H16B	0.6098	−0.1269	0.6260	0.059*
H16C	0.4571	−0.1062	0.6545	0.059*
Li3	0.0076 (4)	0.09502 (17)	0.27226 (13)	0.0285 (7)
N9	0.0996 (2)	0.17062 (9)	0.24202 (7)	0.0297 (4)
C17	0.1786 (3)	0.20528 (9)	0.22427 (8)	0.0269 (4)
C18	0.2810 (3)	0.24923 (11)	0.20127 (9)	0.0366 (5)
H18A	0.3334	0.2736	0.2259	0.055*
H18B	0.2197	0.2760	0.1805	0.055*
H18C	0.3587	0.2277	0.1820	0.055*
N10	0.0918 (3)	0.01963 (9)	0.23909 (7)	0.0337 (4)
C19	0.1617 (3)	−0.01773 (10)	0.22136 (9)	0.0306 (5)
C20	0.2520 (4)	−0.06494 (12)	0.19745 (12)	0.0451 (7)
H20A	0.1834	−0.0893	0.1770	0.068*
H20B	0.3006	−0.0912	0.2216	0.068*
H20C	0.3328	−0.0460	0.1777	0.068*
N11	0.0944 (2)	0.09247 (9)	0.33925 (6)	0.0298 (4)
C21	0.1661 (2)	0.09051 (9)	0.37360 (7)	0.0255 (4)
C22	0.2588 (3)	0.08770 (12)	0.41673 (8)	0.0368 (5)
H22A	0.3248	0.0514	0.4158	0.055*
H22B	0.1903	0.0857	0.4448	0.055*
H22C	0.3242	0.1241	0.4189	0.055*
N12	−0.2267 (2)	0.09405 (10)	0.27100 (7)	0.0338 (4)
C23	−0.3580 (3)	0.09458 (10)	0.27519 (7)	0.0280 (4)
C24	−0.5249 (3)	0.09527 (12)	0.28170 (9)	0.0350 (5)
H24A	−0.5552	0.0623	0.3034	0.053*
H24B	−0.5761	0.0896	0.2506	0.053*
H24C	−0.5565	0.1344	0.2955	0.053*
P1	0.96424 (7)	0.41157 (2)	0.868437 (19)	0.02657 (11)
F1	1.0595 (2)	0.35676 (7)	0.84498 (6)	0.0487 (4)
F2	0.8678 (2)	0.46607 (7)	0.89150 (6)	0.0458 (4)
F3	0.8398 (7)	0.4121 (3)	0.82520 (16)	0.0585 (15)	0.643 (16)
F4	0.8495 (5)	0.3634 (2)	0.8934 (3)	0.0600 (16)	0.643 (16)
F5	1.0745 (8)	0.4087 (3)	0.91135 (16)	0.0769 (19)	0.643 (16)
F6	1.0657 (7)	0.4576 (3)	0.8407 (3)	0.068 (2)	0.643 (16)
F3'	0.8304 (12)	0.3874 (7)	0.8409 (8)	0.096 (6)	0.357 (16)
F4'	0.924 (3)	0.3725 (5)	0.9132 (5)	0.098 (7)	0.357 (16)
F5'	1.1177 (11)	0.4365 (8)	0.8979 (6)	0.099 (6)	0.357 (16)
F6'	1.027 (3)	0.4544 (7)	0.8274 (6)	0.110 (7)	0.357 (16)
P2	0.51359 (7)	0.42066 (2)	0.15009 (2)	0.02640 (12)
F7	0.3841 (2)	0.46339 (8)	0.17316 (7)	0.0521 (4)
F8	0.6435 (2)	0.37953 (9)	0.12640 (9)	0.0696 (6)
F9	0.3792 (3)	0.37675 (13)	0.12999 (14)	0.0440 (11)	0.677 (10)
F10	0.5018 (5)	0.45856 (15)	0.10114 (11)	0.0616 (13)	0.677 (10)
F11	0.6433 (3)	0.46452 (16)	0.16889 (15)	0.0532 (15)	0.677 (10)
F12	0.5178 (6)	0.38244 (17)	0.19771 (12)	0.0787 (17)	0.677 (10)
F9'	0.4171 (14)	0.4138 (7)	0.1035 (3)	0.117 (7)	0.323 (10)
F10'	0.6068 (14)	0.4797 (3)	0.1342 (6)	0.114 (7)	0.323 (10)
F11'	0.6121 (11)	0.4248 (5)	0.1995 (3)	0.095 (5)	0.323 (10)
F12'	0.4302 (12)	0.3621 (3)	0.1656 (5)	0.101 (6)	0.323 (10)
P3	0.02195 (7)	0.23730 (3)	0.64355 (2)	0.02811 (12)
F13	0.1488 (2)	0.28030 (9)	0.66797 (7)	0.0571 (5)
F14	−0.1073 (3)	0.19621 (9)	0.61921 (9)	0.0726 (6)
F15	0.1179 (6)	0.18006 (16)	0.6596 (2)	0.0811 (17)	0.723 (13)
F16	0.1159 (5)	0.2400 (3)	0.59470 (14)	0.0794 (15)	0.723 (13)
F17	−0.0706 (4)	0.2365 (2)	0.69211 (11)	0.0747 (16)	0.723 (13)
F18	−0.0725 (4)	0.29610 (12)	0.62768 (14)	0.0517 (13)	0.723 (13)
F15'	0.1477 (11)	0.1915 (6)	0.6288 (7)	0.086 (6)	0.277 (13)
F16'	0.044 (2)	0.2731 (7)	0.5971 (4)	0.103 (9)	0.277 (13)
F17'	0.008 (2)	0.1978 (7)	0.6921 (3)	0.098 (7)	0.277 (13)
F18'	−0.1088 (11)	0.2809 (6)	0.6638 (7)	0.109 (11)	0.277 (13)
N13	0.5640 (3)	0.14595 (11)	0.74120 (10)	0.0485 (6)
C25	0.6588 (3)	0.11557 (12)	0.72554 (10)	0.0390 (6)
C26	0.7796 (4)	0.07672 (16)	0.70644 (13)	0.0580 (8)
H26A	0.8673	0.0756	0.7289	0.087*
H26B	0.8147	0.0927	0.6755	0.087*
H26C	0.7387	0.0355	0.7021	0.087*
N14	0.5132 (3)	0.01637 (10)	0.93295 (9)	0.0445 (5)
C27	0.5128 (3)	0.04165 (11)	0.89718 (10)	0.0363 (5)
C28	0.5129 (3)	0.07287 (14)	0.85183 (11)	0.0465 (6)
H28A	0.4534	0.0492	0.8284	0.070*
H28B	0.6200	0.0776	0.8405	0.070*
H28C	0.4651	0.1130	0.8557	0.070*
N15	0.9699 (3)	0.17657 (10)	0.46114 (9)	0.0464 (5)
C29	0.9032 (3)	0.21382 (12)	0.47998 (9)	0.0359 (5)
C30	0.8206 (5)	0.26237 (18)	0.50378 (12)	0.0642 (10)
H30A	0.8950	0.2891	0.5200	0.096*
H30B	0.7489	0.2451	0.5275	0.096*
H30C	0.7617	0.2858	0.4800	0.096*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Li1	0.0291 (19)	0.0287 (16)	0.0272 (16)	0.0051 (16)	−0.0016 (15)	−0.0035 (13)
N1	0.0311 (10)	0.0324 (9)	0.0310 (9)	−0.0023 (8)	−0.0011 (8)	0.0010 (7)
C1	0.0247 (10)	0.0278 (9)	0.0284 (10)	−0.0022 (8)	0.0026 (8)	0.0027 (8)
C2	0.0406 (14)	0.0480 (14)	0.0299 (11)	−0.0012 (12)	−0.0090 (10)	−0.0003 (10)
N2	0.0372 (11)	0.0283 (9)	0.0271 (9)	0.0009 (8)	0.0027 (8)	0.0028 (7)
C3	0.0287 (11)	0.0272 (9)	0.0245 (9)	−0.0010 (8)	0.0018 (8)	0.0033 (8)
C4	0.0400 (14)	0.0356 (12)	0.0363 (11)	0.0071 (11)	0.0062 (10)	−0.0050 (10)
N3	0.0324 (11)	0.0371 (10)	0.0317 (9)	−0.0005 (9)	−0.0009 (8)	0.0028 (8)
C5	0.0310 (12)	0.0257 (9)	0.0251 (9)	0.0028 (9)	0.0020 (8)	0.0041 (8)
C6	0.0283 (12)	0.0332 (10)	0.0385 (11)	0.0040 (10)	0.0001 (9)	0.0034 (9)
N4	0.0355 (11)	0.0284 (9)	0.0311 (9)	0.0000 (8)	−0.0012 (8)	0.0016 (7)
C7	0.0278 (11)	0.0283 (10)	0.0254 (9)	0.0073 (8)	−0.0005 (8)	−0.0009 (8)
C8	0.0355 (13)	0.0343 (12)	0.0368 (12)	−0.0045 (10)	0.0047 (10)	0.0055 (9)
Li2	0.036 (2)	0.0274 (16)	0.0315 (17)	−0.0011 (17)	−0.0026 (16)	−0.0001 (13)
N5	0.0297 (10)	0.0480 (12)	0.0309 (9)	−0.0011 (9)	−0.0018 (8)	0.0020 (9)
C9	0.0235 (10)	0.0337 (11)	0.0310 (10)	0.0021 (9)	−0.0035 (8)	0.0005 (9)
C10	0.0336 (12)	0.0372 (11)	0.0324 (11)	0.0017 (10)	0.0033 (9)	0.0008 (10)
N6	0.0360 (11)	0.0303 (9)	0.0343 (10)	−0.0020 (8)	−0.0017 (8)	0.0015 (8)
C11	0.0349 (12)	0.0240 (9)	0.0280 (10)	−0.0012 (9)	−0.0019 (9)	0.0017 (8)
C12	0.0292 (12)	0.0379 (12)	0.0506 (14)	0.0010 (10)	−0.0011 (11)	0.0087 (10)
N7	0.0407 (12)	0.0360 (10)	0.0405 (11)	−0.0043 (10)	−0.0059 (10)	−0.0038 (8)
C13	0.0311 (12)	0.0330 (10)	0.0306 (10)	−0.0027 (10)	−0.0009 (9)	0.0043 (8)
C14	0.0460 (14)	0.0312 (10)	0.0361 (11)	0.0006 (11)	−0.0020 (11)	−0.0048 (9)
N8	0.0426 (12)	0.0353 (10)	0.0378 (10)	0.0028 (10)	−0.0007 (10)	0.0029 (8)
C15	0.0357 (12)	0.0316 (10)	0.0261 (9)	0.0036 (9)	0.0025 (9)	−0.0033 (8)
C16	0.0546 (16)	0.0326 (11)	0.0313 (11)	0.0068 (11)	0.0075 (11)	0.0061 (9)
Li3	0.0279 (19)	0.0322 (16)	0.0255 (15)	−0.0030 (16)	0.0004 (14)	0.0003 (14)
N9	0.0325 (10)	0.0310 (9)	0.0257 (9)	0.0017 (8)	−0.0010 (8)	0.0007 (7)
C17	0.0307 (11)	0.0265 (9)	0.0235 (9)	0.0074 (9)	−0.0027 (8)	−0.0025 (8)
C18	0.0416 (14)	0.0318 (11)	0.0366 (12)	−0.0035 (10)	0.0091 (11)	0.0010 (9)
N10	0.0369 (11)	0.0293 (9)	0.0348 (10)	0.0018 (8)	−0.0004 (9)	0.0012 (7)
C19	0.0292 (11)	0.0290 (10)	0.0336 (11)	−0.0014 (9)	0.0018 (10)	0.0042 (8)
C20	0.0441 (16)	0.0304 (12)	0.0607 (17)	0.0055 (11)	0.0197 (13)	0.0022 (11)
N11	0.0297 (9)	0.0334 (9)	0.0264 (8)	0.0001 (8)	−0.0012 (7)	0.0023 (7)
C21	0.0243 (10)	0.0250 (8)	0.0272 (9)	−0.0001 (8)	0.0044 (8)	0.0000 (8)
C22	0.0350 (12)	0.0425 (13)	0.0329 (11)	−0.0007 (11)	−0.0081 (10)	−0.0022 (10)
N12	0.0301 (10)	0.0391 (10)	0.0322 (9)	0.0002 (9)	0.0004 (8)	0.0001 (8)
C23	0.0314 (12)	0.0284 (9)	0.0241 (9)	−0.0002 (9)	−0.0011 (8)	−0.0008 (8)
C24	0.0276 (11)	0.0402 (11)	0.0373 (11)	−0.0002 (10)	0.0007 (10)	−0.0009 (9)
P1	0.0314 (3)	0.0229 (2)	0.0254 (2)	0.0009 (2)	−0.0007 (2)	−0.00043 (19)
F1	0.0530 (10)	0.0338 (7)	0.0593 (10)	0.0085 (7)	0.0162 (8)	−0.0081 (7)
F2	0.0536 (10)	0.0312 (7)	0.0526 (9)	0.0058 (7)	0.0095 (8)	−0.0099 (7)
F3	0.054 (2)	0.081 (4)	0.0402 (18)	0.017 (3)	−0.0215 (14)	−0.0149 (19)
F4	0.054 (2)	0.0334 (15)	0.092 (4)	−0.0029 (15)	0.031 (2)	0.012 (2)
F5	0.083 (4)	0.099 (4)	0.048 (2)	0.014 (3)	−0.044 (2)	−0.006 (2)
F6	0.052 (2)	0.0342 (19)	0.118 (6)	−0.0092 (16)	0.040 (3)	0.018 (3)
F3'	0.037 (3)	0.083 (8)	0.169 (16)	0.000 (5)	−0.033 (7)	−0.080 (9)
F4'	0.174 (17)	0.050 (5)	0.070 (6)	0.045 (7)	0.087 (8)	0.036 (4)
F5'	0.040 (4)	0.120 (9)	0.137 (10)	0.033 (5)	−0.038 (5)	−0.103 (8)
F6'	0.210 (18)	0.050 (6)	0.070 (7)	0.041 (9)	0.089 (9)	0.028 (4)
P2	0.0241 (3)	0.0235 (2)	0.0317 (3)	0.0000 (2)	−0.0001 (2)	−0.00195 (19)
F7	0.0391 (9)	0.0438 (9)	0.0732 (12)	0.0021 (7)	0.0123 (9)	−0.0213 (8)
F8	0.0347 (9)	0.0619 (11)	0.1122 (17)	0.0078 (9)	0.0047 (10)	−0.0483 (12)
F9	0.0313 (12)	0.0368 (15)	0.064 (2)	−0.0071 (10)	0.0013 (13)	−0.0184 (14)
F10	0.079 (3)	0.061 (2)	0.0447 (15)	−0.0105 (19)	0.0114 (16)	0.0156 (13)
F11	0.0272 (12)	0.048 (2)	0.085 (3)	−0.0038 (12)	−0.0091 (15)	−0.033 (2)
F12	0.120 (4)	0.064 (2)	0.0523 (17)	0.007 (3)	−0.024 (2)	0.0250 (16)
F9'	0.109 (9)	0.177 (16)	0.064 (5)	0.048 (12)	−0.043 (6)	−0.033 (8)
F10'	0.098 (9)	0.044 (4)	0.200 (17)	−0.015 (4)	0.075 (11)	0.031 (6)
F11'	0.088 (6)	0.137 (11)	0.060 (5)	0.028 (7)	−0.035 (5)	−0.023 (6)
F12'	0.097 (8)	0.045 (4)	0.160 (15)	−0.029 (4)	0.055 (10)	0.004 (5)
P3	0.0297 (3)	0.0256 (2)	0.0290 (2)	0.0024 (2)	−0.0014 (2)	0.00179 (19)
F13	0.0469 (10)	0.0572 (10)	0.0673 (12)	−0.0074 (9)	−0.0192 (9)	−0.0042 (9)
F14	0.0601 (13)	0.0539 (11)	0.1037 (17)	−0.0136 (10)	−0.0200 (12)	−0.0275 (11)
F15	0.087 (3)	0.0463 (16)	0.110 (4)	0.0323 (18)	−0.012 (3)	0.024 (2)
F16	0.080 (2)	0.112 (4)	0.0463 (17)	0.023 (2)	0.0308 (16)	0.004 (2)
F17	0.073 (2)	0.106 (4)	0.0446 (15)	0.003 (3)	0.0289 (15)	0.0200 (19)
F18	0.059 (2)	0.0370 (12)	0.059 (2)	0.0187 (12)	−0.0195 (18)	0.0046 (12)
F15'	0.044 (4)	0.073 (8)	0.140 (14)	0.017 (5)	0.009 (6)	−0.049 (9)
F16'	0.151 (18)	0.098 (10)	0.061 (6)	−0.075 (12)	−0.047 (10)	0.040 (7)
F17'	0.136 (15)	0.100 (10)	0.059 (5)	−0.060 (11)	−0.015 (7)	0.024 (6)
F18'	0.048 (5)	0.099 (12)	0.18 (2)	0.020 (5)	−0.014 (7)	−0.105 (15)
N13	0.0464 (14)	0.0421 (12)	0.0570 (15)	−0.0026 (11)	−0.0012 (12)	−0.0039 (11)
C25	0.0411 (14)	0.0352 (11)	0.0406 (13)	−0.0076 (11)	−0.0069 (11)	0.0036 (10)
C26	0.0548 (19)	0.0545 (17)	0.065 (2)	0.0112 (16)	0.0057 (16)	−0.0071 (15)
N14	0.0473 (14)	0.0399 (11)	0.0462 (12)	−0.0034 (10)	−0.0048 (11)	−0.0132 (9)
C27	0.0263 (11)	0.0322 (10)	0.0504 (14)	−0.0019 (9)	−0.0028 (11)	−0.0155 (10)
C28	0.0307 (12)	0.0523 (15)	0.0566 (16)	−0.0006 (12)	−0.0023 (12)	0.0015 (12)
N15	0.0504 (14)	0.0382 (11)	0.0507 (13)	0.0017 (11)	−0.0040 (12)	−0.0021 (10)
C29	0.0339 (13)	0.0417 (13)	0.0321 (11)	0.0010 (10)	−0.0016 (10)	0.0077 (10)
C30	0.074 (2)	0.076 (2)	0.0431 (16)	0.036 (2)	0.0067 (16)	0.0003 (16)

Geometric parameters (Å, º) top

Li1—N3	2.007 (5)	C20—H20A	0.9800
Li1—N1	2.012 (4)	C20—H20B	0.9800
Li1—N2	2.036 (4)	C20—H20C	0.9800
Li1—N4	2.063 (4)	N11—C21	1.140 (3)
N1—C1	1.141 (3)	C21—C22	1.444 (3)
C1—C2	1.441 (3)	C22—H22A	0.9800
C2—H2A	0.9800	C22—H22B	0.9800
C2—H2B	0.9800	C22—H22C	0.9800
C2—H2C	0.9800	N12—C23	1.136 (3)
N2—C3	1.134 (3)	C23—C24	1.448 (3)
C3—C4	1.458 (3)	C24—H24A	0.9800
C4—H4A	0.9800	C24—H24B	0.9800
C4—H4B	0.9800	C24—H24C	0.9800
C4—H4C	0.9800	P1—F3'	1.484 (10)
N3—C5	1.137 (3)	P1—F5	1.528 (5)
C5—C6	1.456 (3)	P1—F6	1.544 (6)
C6—H6A	0.9800	P1—F4'	1.555 (7)
C6—H6B	0.9800	P1—F6'	1.577 (14)
C6—H6C	0.9800	P1—F2	1.5929 (16)
N4—C7	1.129 (3)	P1—F1	1.5975 (16)
C7—C8	1.457 (3)	P1—F4	1.607 (4)
C8—H8A	0.9800	P1—F3	1.612 (5)
C8—H8B	0.9800	P1—F5'	1.650 (8)
C8—H8C	0.9800	P2—F12'	1.535 (6)
Li2—N7	2.009 (4)	P2—F9'	1.548 (7)
Li2—N6	2.021 (5)	P2—F11	1.565 (3)
Li2—N8	2.038 (4)	P2—F12	1.571 (3)
Li2—N5	2.048 (5)	P2—F8	1.5823 (18)
N5—C9	1.128 (3)	P2—F10'	1.589 (7)
C9—C10	1.461 (3)	P2—F7	1.5933 (17)
C10—H10A	0.9800	P2—F10	1.602 (3)
C10—H10B	0.9800	P2—F9	1.608 (2)
C10—H10C	0.9800	P2—F11'	1.620 (7)
N6—C11	1.132 (3)	P3—F16'	1.526 (8)
C11—C12	1.451 (4)	P3—F15'	1.535 (8)
C12—H12A	0.9800	P3—F15	1.570 (3)
C12—H12B	0.9800	P3—F17	1.571 (3)
C12—H12C	0.9800	P3—F18'	1.582 (8)
N7—C13	1.145 (3)	P3—F16	1.585 (3)
C13—C14	1.457 (3)	P3—F14	1.586 (2)
C14—H14A	0.9800	P3—F18	1.590 (2)
C14—H14B	0.9800	P3—F13	1.5967 (19)
C14—H14C	0.9800	P3—F17'	1.614 (9)
N8—C15	1.132 (3)	N13—C25	1.141 (4)
C15—C16	1.461 (3)	C25—C26	1.447 (4)
C16—H16A	0.9800	C26—H26A	0.9800
C16—H16B	0.9800	C26—H26B	0.9800
C16—H16C	0.9800	C26—H26C	0.9800
Li3—N11	2.012 (4)	N14—C27	1.142 (4)
Li3—N12	2.017 (4)	C27—C28	1.438 (4)
Li3—N9	2.025 (4)	C28—H28A	0.9800
Li3—N10	2.032 (4)	C28—H28B	0.9800
N9—C17	1.135 (3)	C28—H28C	0.9800
C17—C18	1.456 (3)	N15—C29	1.129 (3)
C18—H18A	0.9800	C29—C30	1.444 (4)
C18—H18B	0.9800	C30—H30A	0.9800
C18—H18C	0.9800	C30—H30B	0.9800
N10—C19	1.132 (3)	C30—H30C	0.9800
C19—C20	1.458 (3)

N3—Li1—N1	114.0 (2)	F6—P1—F1	90.0 (3)
N3—Li1—N2	111.4 (2)	F4'—P1—F1	91.5 (3)
N1—Li1—N2	108.14 (19)	F6'—P1—F1	88.7 (6)
N3—Li1—N4	109.27 (19)	F2—P1—F1	179.44 (11)
N1—Li1—N4	107.83 (19)	F3'—P1—F4	60.7 (8)
N2—Li1—N4	105.79 (19)	F5—P1—F4	90.9 (3)
C1—N1—Li1	173.2 (2)	F6—P1—F4	175.3 (4)
N1—C1—C2	179.7 (3)	F6'—P1—F4	156.7 (8)
C1—C2—H2A	109.5	F2—P1—F4	90.04 (19)
C1—C2—H2B	109.5	F1—P1—F4	89.75 (19)
H2A—C2—H2B	109.5	F5—P1—F3	176.3 (3)
C1—C2—H2C	109.5	F6—P1—F3	89.8 (4)
H2A—C2—H2C	109.5	F4'—P1—F3	117.2 (9)
H2B—C2—H2C	109.5	F6'—P1—F3	71.4 (8)
C3—N2—Li1	172.3 (2)	F2—P1—F3	87.1 (2)
N2—C3—C4	178.4 (2)	F1—P1—F3	92.3 (2)
C3—C4—H4A	109.5	F4—P1—F3	85.5 (3)
C3—C4—H4B	109.5	F3'—P1—F5'	177.7 (5)
H4A—C4—H4B	109.5	F6—P1—F5'	65.1 (8)
C3—C4—H4C	109.5	F4'—P1—F5'	87.8 (7)
H4A—C4—H4C	109.5	F6'—P1—F5'	83.6 (8)
H4B—C4—H4C	109.5	F2—P1—F5'	88.0 (3)
C5—N3—Li1	174.2 (2)	F1—P1—F5'	92.5 (3)
N3—C5—C6	179.3 (3)	F4—P1—F5'	119.7 (7)
C5—C6—H6A	109.5	F3—P1—F5'	154.4 (7)
C5—C6—H6B	109.5	F12'—P2—F9'	84.5 (8)
H6A—C6—H6B	109.5	F12'—P2—F11	139.1 (6)
C5—C6—H6C	109.5	F9'—P2—F11	136.3 (6)
H6A—C6—H6C	109.5	F12'—P2—F12	47.5 (5)
H6B—C6—H6C	109.5	F9'—P2—F12	131.9 (6)
C7—N4—Li1	171.2 (2)	F11—P2—F12	91.7 (2)
N4—C7—C8	179.3 (2)	F12'—P2—F8	88.2 (3)
C7—C8—H8A	109.5	F9'—P2—F8	88.5 (4)
C7—C8—H8B	109.5	F11—P2—F8	89.29 (13)
H8A—C8—H8B	109.5	F12—P2—F8	91.75 (18)
C7—C8—H8C	109.5	F12'—P2—F10'	177.5 (6)
H8A—C8—H8C	109.5	F9'—P2—F10'	96.6 (9)
H8B—C8—H8C	109.5	F12—P2—F10'	131.4 (7)
N7—Li2—N6	104.1 (2)	F8—P2—F10'	89.6 (3)
N7—Li2—N8	109.8 (2)	F12'—P2—F7	93.1 (3)
N6—Li2—N8	107.4 (2)	F9'—P2—F7	91.2 (4)
N7—Li2—N5	112.4 (2)	F11—P2—F7	90.05 (12)
N6—Li2—N5	111.3 (2)	F12—P2—F7	89.46 (17)
N8—Li2—N5	111.4 (2)	F8—P2—F7	178.64 (13)
C9—N5—Li2	175.7 (2)	F10'—P2—F7	89.1 (3)
N5—C9—C10	178.4 (2)	F12'—P2—F10	130.2 (6)
C9—C10—H10A	109.5	F9'—P2—F10	45.8 (6)
C9—C10—H10B	109.5	F11—P2—F10	90.6 (2)
H10A—C10—H10B	109.5	F12—P2—F10	177.5 (2)
C9—C10—H10C	109.5	F8—P2—F10	89.23 (16)
H10A—C10—H10C	109.5	F10'—P2—F10	50.9 (6)
H10B—C10—H10C	109.5	F7—P2—F10	89.58 (14)
C11—N6—Li2	167.4 (2)	F11—P2—F9	178.8 (2)
N6—C11—C12	178.9 (3)	F12—P2—F9	89.4 (2)
C11—C12—H12A	109.5	F8—P2—F9	91.13 (11)
C11—C12—H12B	109.5	F10'—P2—F9	139.1 (7)
H12A—C12—H12B	109.5	F7—P2—F9	89.50 (12)
C11—C12—H12C	109.5	F10—P2—F9	88.3 (2)
H12A—C12—H12C	109.5	F12'—P2—F11'	93.0 (7)
H12B—C12—H12C	109.5	F9'—P2—F11'	177.4 (8)
C13—N7—Li2	169.3 (3)	F11—P2—F11'	46.2 (4)
N7—C13—C14	179.8 (3)	F12—P2—F11'	45.6 (4)
C13—C14—H14A	109.5	F8—P2—F11'	91.0 (3)
C13—C14—H14B	109.5	F10'—P2—F11'	85.9 (8)
H14A—C14—H14B	109.5	F7—P2—F11'	89.4 (3)
C13—C14—H14C	109.5	F10—P2—F11'	136.7 (5)
H14A—C14—H14C	109.5	F9—P2—F11'	135.0 (5)
H14B—C14—H14C	109.5	F16'—P3—F15'	91.3 (9)
C15—N8—Li2	169.9 (3)	F16'—P3—F15	126.0 (8)
N8—C15—C16	179.7 (3)	F16'—P3—F17	143.1 (8)
C15—C16—H16A	109.5	F15'—P3—F17	125.5 (8)
C15—C16—H16B	109.5	F15—P3—F17	90.7 (3)
H16A—C16—H16B	109.5	F16'—P3—F18'	94.6 (10)
C15—C16—H16C	109.5	F15'—P3—F18'	174.1 (9)
H16A—C16—H16C	109.5	F15—P3—F18'	139.3 (8)
H16B—C16—H16C	109.5	F17—P3—F18'	48.6 (8)
N11—Li3—N12	112.78 (19)	F15'—P3—F16	55.6 (7)
N11—Li3—N9	105.30 (19)	F15—P3—F16	90.3 (3)
N12—Li3—N9	113.1 (2)	F17—P3—F16	178.5 (3)
N11—Li3—N10	105.50 (19)	F18'—P3—F16	130.3 (8)
N12—Li3—N10	109.9 (2)	F16'—P3—F14	91.1 (4)
N9—Li3—N10	109.91 (18)	F15'—P3—F14	90.3 (4)
C17—N9—Li3	165.3 (2)	F15—P3—F14	91.9 (2)
N9—C17—C18	179.4 (3)	F17—P3—F14	90.36 (18)
C17—C18—H18A	109.5	F18'—P3—F14	90.0 (3)
C17—C18—H18B	109.5	F16—P3—F14	90.7 (2)
H18A—C18—H18B	109.5	F16'—P3—F18	53.8 (8)
C17—C18—H18C	109.5	F15'—P3—F18	145.1 (8)
H18A—C18—H18C	109.5	F15—P3—F18	178.9 (2)
H18B—C18—H18C	109.5	F17—P3—F18	89.4 (2)
C19—N10—Li3	168.7 (2)	F16—P3—F18	89.5 (2)
N10—C19—C20	178.6 (3)	F14—P3—F18	89.17 (14)
C19—C20—H20A	109.5	F16'—P3—F13	88.3 (4)
C19—C20—H20B	109.5	F15'—P3—F13	91.2 (4)
H20A—C20—H20B	109.5	F15—P3—F13	89.64 (19)
C19—C20—H20C	109.5	F17—P3—F13	89.21 (17)
H20A—C20—H20C	109.5	F18'—P3—F13	88.6 (3)
H20B—C20—H20C	109.5	F16—P3—F13	89.73 (19)
C21—N11—Li3	169.0 (2)	F14—P3—F13	178.36 (12)
N11—C21—C22	179.2 (2)	F18—P3—F13	89.25 (13)
C21—C22—H22A	109.5	F16'—P3—F17'	176.8 (9)
C21—C22—H22B	109.5	F15'—P3—F17'	85.7 (8)
H22A—C22—H22B	109.5	F15—P3—F17'	50.9 (7)
C21—C22—H22C	109.5	F18'—P3—F17'	88.5 (9)
H22A—C22—H22C	109.5	F16—P3—F17'	141.2 (7)
H22B—C22—H22C	109.5	F14—P3—F17'	90.0 (4)
C23—N12—Li3	173.0 (2)	F18—P3—F17'	129.3 (7)
N12—C23—C24	178.7 (2)	F13—P3—F17'	90.7 (4)
C23—C24—H24A	109.5	N13—C25—C26	179.1 (3)
C23—C24—H24B	109.5	C25—C26—H26A	109.5
H24A—C24—H24B	109.5	C25—C26—H26B	109.5
C23—C24—H24C	109.5	H26A—C26—H26B	109.5
H24A—C24—H24C	109.5	C25—C26—H26C	109.5
H24B—C24—H24C	109.5	H26A—C26—H26C	109.5
F3'—P1—F5	150.8 (8)	H26B—C26—H26C	109.5
F3'—P1—F6	114.5 (9)	N14—C27—C28	179.3 (3)
F5—P1—F6	93.8 (4)	C27—C28—H28A	109.5
F3'—P1—F4'	92.6 (7)	C27—C28—H28B	109.5
F5—P1—F4'	59.1 (8)	H28A—C28—H28B	109.5
F6—P1—F4'	152.9 (9)	C27—C28—H28C	109.5
F3'—P1—F6'	96.0 (9)	H28A—C28—H28C	109.5
F5—P1—F6'	112.3 (8)	H28B—C28—H28C	109.5
F4'—P1—F6'	171.4 (9)	N15—C29—C30	178.8 (3)
F3'—P1—F2	94.3 (4)	C29—C30—H30A	109.5
F5—P1—F2	92.2 (2)	C29—C30—H30B	109.5
F6—P1—F2	90.2 (3)	H30A—C30—H30B	109.5
F4'—P1—F2	88.6 (3)	C29—C30—H30C	109.5
F6'—P1—F2	91.3 (6)	H30A—C30—H30C	109.5
F3'—P1—F1	85.2 (4)	H30B—C30—H30C	109.5
F5—P1—F1	88.3 (2)

Experimental details

Crystal data
Chemical formula	[Li(C₂H₃N)₄]PF₆·C₂H₃N
M_r	357.18
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	110
a, b, c (Å)	8.6064 (3), 21.9864 (8), 27.8721 (10)
V (Å³)	5274.1 (3)
Z	12
Radiation type	Mo Kα
µ (mm⁻¹)	0.22
Crystal size (mm)	0.67 × 0.40 × 0.27

Data collection
Diffractometer	Bruker–Nonius Kappa Axis X8 APEXII diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.870, 0.944
No. of measured, independent and observed [I > 2σ(I)] reflections	128974, 17572, 13189
R_int	0.060
(sin θ/λ)_max (Å⁻¹)	0.737

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.054, 0.157, 1.03
No. of reflections	17572
No. of parameters	749
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.46, −0.31
Absolute structure	Flack (1983), 7916 Friedel pairs
Absolute structure parameter	0.45 (7)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), cif2tables.py (Boyle, 2008).

Acknowledgements

The authors wish to thank the Department of Chemistry of North Carolina State University and the State of North Carolina for funding the purchase of the APEXII diffractometer.

References

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